Best known for its banks, airport and Super Bowl-quality football team, Charlotte has never been mistaken as a center for homegrown tech companies with market-moving potential. Doug Lebda’s LendingTree, a pioneer in the online loan market, delivered a $44 million IPO in 2000, then almost collapsed in the 2007-09 recession before recovering. Ric Elias and Dan Feldstein started Red Ventures in Charlotte, moved its headquarters to South Carolina, and the business is growing rapidly as internet marketing explodes. Dave Jones’ Peak 10 grew into a data-center leader that employs about 200 people in Charlotte and is now owned by a San Francisco private-equity group. Now, the short list of tech successes is gaining an entrant poised to accelerate the city’s reputation as a startup hotspot.

AvidXchange Inc.’s revenue is growing at an 80% clip this year, and the company now employs 800 people, compared with 75 in 2011 and 300 in January 2015. It raised $225 million last year from some of the most successful U.S. tech investors, pushing its valuation past $500 million. It was triple the venture-capital money raised from U.S. investors by any other North Carolina business since 2010, according to PricewaterhouseCoopers and the National Venture Capital Association. Its board is now stocked with veteran executives who include a former Visa president, a co-founder of Capital One Financial and a venture capitalist who made hundreds of millions of dollars when FitBit went public.

Most companies grow fast initially, then plateau as the numbers get larger. The reverse has happened at the company co-founded in 2000 by Midwestern transplants Michael Praeger and David Miller. Started as the dotcom bubble burst, AvidXchange is no instant success. It grew modestly during its first decade or so and raised about $20 million in its first 14 years, with most of the investment coming from founders, private individuals and a now-defunct Charlotte venture-capital fund.

“Avid is a fascinating example of a large company, growing extremely quick, that is hidden in plain sight,” venture-capital investor Brad Feld said after his Boulder, Colo.-based company, Foundry Group, joined with Bain Capital Ventures and others in last year’s financing. As one of the state’s fastest-growing tech companies, “It’s on track to be a very important payment intermediary in the overall financial infrastructure.”

Translating that into English, AvidXchange shuffles money between businesses, befitting Charlotte’s strong suit as a finance center. It automates accounts payable, speeding up a decades-old trend of squeezing paper checks out of society, replaced by a few keystrokes on computers, tablets or phones. Accounts payable may rank among the world’s least sexy topics, but no one can doubt its ubiquity: Praeger notes that every business owner ultimately worries about cash flow and paying the bills.

AvidXchange marked Bain Capital’s first $100 million-plus investment in a financial-technology company, says managing director Matt Harris, an AvidXchange director. Bain is a New York-based company co-founded by Mitt Romney in 1984. “They have more than met our expectations. The growth has been phenomenal.” Feld, whose company is best known for receiving $282 million when FitBit went public, says, “A year later, we are delighted with our investment.”

The key to AvidXchange’s growth is Praeger, says Harris. “Mike has a rare combination as a visionary and also a pragmatist. Usually you get someone who is dreamy with a great vision, but they can’t execute. Or others can get things done, but they don’t dream big. Mike has this great down-to-earth quality, but his ambition is colossal.”

Praeger, 48, took a circuitous route to Charlotte. He hails from Sheboygan County, Wis., home of Kohler bathroom products and Johnsonville bratwurst. It’s 65 miles south of Green Bay, where his family has owned Packers season tickets for decades. He received a finance degree at Georgetown University, then worked in Boston for Summit Partners, a venture-capital group. He later started and sold two small companies and made contacts in the Massachusetts tech community, including Feld. But Praeger and his wife, Cindy, whom he met at Georgetown and also has started companies, tired of New England weather.

Backed by months of study, they developed a list of five balmier cities offering the best chance for a business to thrive. On Labor Day weekend of 1996, they decided on Charlotte, though they knew another North Carolina city had a stronger tech reputation. “Raleigh was on the list, but it seemed very spread out and we wanted to be part of a city structure,” he says. They bought land at Lake Norman and built a home where they still reside.

After starting and selling an online résumé business, Praeger and his friend Miller opened a software-development company in April 2000. They hired UNC Charlotte grad Chris Tinsley as chief technology officer and their initial offering automated the business of buying stuff, or procurement. Two years into the business, a customer told Praeger he liked the software but was frustrated with his accounts payable process. “The client told Mike, ‘I like what you have, but can you do something with these invoices because we’ve got paper flowing all over,’” says Alan Harris, one of the first 15 people hired at the company and now an account manager based in New Jersey.

Tinsley added the new feature to AvidXchange’s product, and customers found that the tweak was more valuable than the initial offering. This was a decade ago, before consumer online bill payment was entrenched. It remained a tough sell with the target market of small and midsized business owners. “Part of the struggle was how do you create a sense of need, because people had been paying bills the same way for 30 years,” Alan Harris says.

To expand, Praeger hoped to raise $10 million. The dotcom collapse of 2000-02, which sunk the tech-heavy Nasdaq index by more than 75%, nixed that plan. “In 1999, everyone wanted to be an angel investor,” he recalls. “Five years later, no one wanted to be an angel investor.” Fortunately, Concord-based CT Communications and a 50-person group including Hugh McColl Jr. and Elliott Crutchfield, saw promise in Praeger, who raised about $1.5 million. About $250,000 came from Charlotte Angel Partners, says its founder, Brent Kulman, who now works for a Winston-Salem-based private-equity company.

With cash flow tight in its early years, AvidXchange asked customers for two months of payments in advance. Everyone agreed, but six months later, the business again struggled.

“We asked for three months of advance payments and then, a year later, we asked for a full year. Eighty percent agreed because they saw the value in what we were doing,” Praeger says. “It was the cheapest capital available.” Annual contracts now average about $40,000 to $50,000, with a 98% renewal rate.

Praeger showed unusual tenacity during those early years, says Alan Harris. “He’s one of the most energetic and optimistic human beings I’ve ever met. We’ve gone through some circumstances where we wondered, what are we going to do and are we going to make it? I never saw him sweat.”

Praeger wasn’t alone in facing the pressures of a startup. “David [Miller] was a tech guy who really saw the future of SaaS [a catch-all phrase that stands for software as a service rather than as a one-time product sale],” Harris says. When some key clients offered lots of money for the ability to integrate the product on their own servers, Miller resisted. The deals would have paid off handsomely initially but cut future revenue growth. “We had some very big opportunities, and Mike said yes. But David said no, that’s not how we are building this company.”

Miller left as a full-time employee in 2011, noting in a blog post then that he wasn’t having fun. He told employees at the time, “I’m not a guy who does well in a company growing from 50 to 500 people.” Stepping back and enabling Praeger to lead was in the company’s best interest, he added. He now advises startups.

Client inertia — some payables clerks still prefer paper — remains AvidXchange’s biggest challenge, Praeger says, though the sales pitch is easier with younger people moving into senior finance jobs. Millennials are confounded at the notion of paper checks. “A lot of old line accounts payable clerks are retiring, and rather than replacing them, in some cases, companies are choosing to automate.”

AvidXchange focuses on the 340,000 U.S. firms with sales of $5 million to $1 billion, with competitors including Finland-based Basware Corp., and Cambridge, Mass.-based Mineral Tree Inc. With less than 5% signed up now, Praeger and his backers see enormous growth potential.

Banks are viewed more as partners than as competitors. “Banks have great strengths, but building elegant software isn’t what banks are really good at,” Harris says. Most businesses have relations with several financial institutions with cash management systems that often aren’t compatible. Having an independent technology that spans many systems is a key advantage for AvidXchange.

Pressed on why banks haven’t offered a similar product, Praeger says they’ve focused on retail banking, rather than business-to-business transactions. “There was all of this noise around online bill payments involving consumers, but there wasn’t much talk about business bill payments”

With a chance to “revolutionize how businesses pay their bills,” Praeger has recruited senior leaders who previously worked at much larger companies. Only three of 12 senior managers have worked at AvidXchange for more than five years. Notable hires include Tom Spencer, who worked for Intuit for 15 years and led sales of its TurboTax and QuickBooks products, and Todd Cunningham, a former senior HR executive at Bank of America.

Promising companies “need to pay up for what you will need in three years,” Praeger told a Charlotte business group earlier this year. “It’s hard to, because people are expensive. But those are the people that are helping us scale up.”

AvidXchange’s board also attests to the company’s potential. Nigel Morris co-founded Capital One Financial in 1994 and is managing partner of a Virginia-based private-equity fund. He is also a director of Red Ventures. Hans Morris (no relation) is a former president of Visa and now a managing partner of a New York-based venturecapital firm. Institutional Investor magazine ranks Hans Morris and Bain’s Harris among the 35 most influential financial-technology investors.

Praeger stayed loyal to Charlotte when the company looked to expand in 2014. It spurned a more lucrative incentives offer from South Carolina, opting for a $10 million package from Charlotte and the state, hinging on hiring 603 people from 2015 to 2018. Pay is expected to average more than $61,500. Praeger wanted a campus in or near downtown Charlotte, which he views as more attractive than the suburbs for his staff.

AvidXchange landed at the N.C. Music Factory, a collection of bars, restaurants and entertainment venues in a rehabbed textile and asbesto manufacturing space, a mile north of downtown. It is adding a six-story building on a former parking lot that has space for about 1,000 people when it opens next summer. The workers are a mix of techies and support servicers. Other key offices are in New Jersey, Texas and Utah.

The new building includes a first floor entirely devoted to employee amenities such as exercise facilities and a food court, and it may be filled to capacity soon after it opens, Praeger says. A work-hard, play-hard style is emphasized with cornhole boards and pingpong tables dotting its main Charlotte office.

“Creating a good work and life balance is important,” says Praeger, a longtime leader of the Queen City Athletic Association, which sponsors youth basketball teams. His son, Chase, is a varsity player at a local high school. “We asked if we were creating the right place where [employees] want to spend so much of their time.”

AvidXchange’s impact is just starting to affect Charlotte, says Dan Roselli, founder of the Packard Place business incubator that is now part of the HQ Community. “They are the poster child for [financial tech] innovation and what we want to do in Charlotte,” he says. “Like all good entrepreneurs, Mike is focused and tenacious. He is scrappy and just finds a way to get things done.”

Basing the company in Charlotte is a big advantage because the labor costs are lower than California, New York and other tech centers, Bain’s Harris says. While major cities help promising companies attract the first 15 or 20 employees, “scaling to 1,000 people is prohibitively expensive. Charlotte has a depth of high-quality talent, and there is a great work ethic.”

Private-equity companies seek a minimum return of three to five times their outlays, so Bain and others are betting that AvidXchange could be worth more than $1.5 billion within the next five years, two local investment bankers say. That would quench Charlotte’s desire for a breakout tech success.